Forty years ago this month, Canada went to war. It started as a friendly cultural exchange intended to signal a thawing of East-West relations and firmly establish Canada as the world’s true hockey superpower. But the cream of the professional crop stumbled badly, and the eight-game series exploded into a Cold War proxy that Canadians feared they might very well lose. Then the tide magically turned, and today the victors are remembered as national heroes. Here is their story.

How did a game become a war?

At its beginning, few saw the Summit Series as anything more than a working vacation for Canada's hockey pros. Everyone, including the Soviets, agreed on a few likely outcomes: Phil Esposito and the boys would politely embarrass the Communists; the Soviets, dominant in international hockey for a decade, would treat it as a learning experience; diplomats would tout the matches as a kind of cultural exchange that could thaw the Cold War.

In dozens of interviews, the figures who planned it and played it gave a minute-by-minute account of how the Summit Series unfolded.